A variety of medical problems require cauterization, which is the burning, scarring, or cutting of tissue by means of heat, cold, electric current, or caustic chemicals. For example, during surgery bleeding from severed arteries may be stemmed by cautery, or tissue may be cut with a cautery cutter to reduce the bleeding that may occur with a non-cauterizing tissue cutter.
Providing a cauterizing capability within a medical device is often conveniently accomplished by including one or more electrical conductors that may be placed in contact with tissue at a treatment site to form an electrical circuit that includes the tissue. When high frequency current is activated within the circuit, via an attached electrocautery generator, tissue is heated and cauterized. Such devices are known as electrocautery devices.
In flexible gastrointestinal (GI) endoscopy, catheter-based electrocautery devices are often used for various treatments. For example, an electrocautery snare provides a conductive wire loop that may be used to lasso a polyp in the colon and cut tissue at the base of the polyp in order to resect it. Electrocautery snares are often used in the esophagus to remove dysplastic mucosal tissue, known as Barrett's Esophagus, which can become cancerous if untreated. An electrocautery probe includes a small head, with exposed electrodes, that may be placed in contact with tissue to cauterize very small areas. Such probes are often used to stem small bleeding sites throughout the GI tract. Biopsy forceps include electrified cups that cauterize tissue as small samples are collected. Electrocautery sphincterotomes include an electrified, tensionable cutting wire to controllably cut the Sphincter of Otti, along a prescribed plane, to improve access to the biliary and pancreatic ductal systems.
Cautery devices available for use during flexible GI endoscopy, such as the snares, probes, forceps, and sphincterotomes described above, are not well suited for cauterizing large surface areas, such as large sections of Barrett's Esophagus, large bleeding sites such as a large gastric ulcer, or following resection of a large sessile polyp. Use of the available devices to treat such areas often requires repeated cauterizations, which can unreasonably increase the procedure time and need for sedation. Moreover, of the other currently available cautery devices, such as scalpels, clamps, staplers and scissors, that may be capable of treating large areas of tissue, none are generally adapted to fit through the accessory channel of a flexible GI endoscope.
In view of the drawbacks of the current technology, there is an unmet need for a cautery catheter that can fit through an endoscope accessory channel and which can rapidly and effectively cauterize treatment sites having relatively large surface areas.